Not applicable
1. Field of Invention
This invention relates to mechanical, automatic or robotic devices which permit people with disabilities to feed themselves, specifically to self-feeding devices which permit handling a wide variety of foods under programmable control with a multiplicity of possible utensils and user interfaces.
2. Discussion of Prior Art
U.S. Pat. No. 3,885,681, Pasquale M. Maucino, 1974, discloses a non powered feeding device which requires the user to grasp a mouth-piece and maneuver a spoon to pick up food, then maneuver the spoon onto a fixed support. The user then releases the mouthpiece and eats the food. This requires the user to have a wide range of head motions which limits its use to a small set of those with severe paralysis. It is not a dignified way to eat.
U.S. Pat. No. 3,907,126, Garland S. Sydnur, Sr., 1974, discloses a powered mechanical device consisting of a table with columns holding food. The user triggers the food to be pushed forward in a column to a hole through which it drops down onto the spoon which then pivots out to a position where the user can reach it. This is a difficult apparatus to set up and maintain. It uses no standard dishes, in fact no dishes at all. One could not use this and eat at table with family or friends.
U.S. Pat. No. 4,162,868, Stapleton, Browne and Weatherholt, 1979, discloses a mechanical, powered self-feeding device utilizing containers of food and a spoon which moves in a reciprocating straight path. Food drops from the bottom of a container onto the spoon and the spoon them moves toward the user""s mouth. This device works only with a limited variety of foods. The user must eat with the whole apparatus inches from his/her nose. Not very dignified.
U.S. Pat. No. 4,277,213, William H. Morewood, 1981, discloses a mechanical, powered, self-feeding device for automatically lifting food from the eating surface of a plate to an eating position located above the plate. The spoon is moved to a rotating plate or a bowl by a set of cams and levers and then to a position where the user can reach it A pusher arm pushes food onto the spoon.
U.S. Pat. No. 5,037,261, William H. Morewood, 1991, discloses an improved spoon support mechanism for the device disclosed in U.S. Pat. No. 4,277,213, William H. Morewood, 1981.
The device specified in these two patents is currently on the market as the Winsford Feeder. It works with only a limited variety of foods. It has only a single method of control. It cannot handle multiple food holding vessels at one time. It cannot handle sandwiches. It cannot operate utensils such as tongs.
U.S. Pat. No. 4,433,950, Hanger and Walker, 1984, discloses a mechanical, powered self-feeding device wherein a pivoted arm carries a spoon between a raised position for eating and a lower position for filling from a rotating plate.
U.S. Pat. No. 5,282,711, Eric A. Frische, 1994, discloses a powered self-feeding device consisting of a rotating, compartmented food receptacle. A feeding utensil mounted on a rod is moved down to the food receptacle to get food and up to the eating position by means of levers.
U.S. Pat. No. 4,522,543, Eric Robinson, 1985, discloses a powered, mechanic self-feeding device with a spoon mounted on a rod which is moved into a food receptacle and up to an eating position by mechanical means.
French Pat. No. 2,692,460, Loustalot Franciose, 1992 discloses a powered, mechanical self feeding device which utilizes a rotating food receptacle to move food into a tilted spoon which is raised into eating position by mechanical means.
The previous six patents above, U.S. Pat. Nos. 4,277,213, 5,037,261, 4,433,950, 5,282,711, 4,522,543, and 2,692,460 are limited to a single food pick-up path because path control is strictly mechanical i.e it cannot be flexibly programmed with a microprocessor. This limits their use to the few types of food which can be reliably picked up by the chosen utensil path. None of them can pick up and operate a utensil such as a tong. None of them can cut food. None of them can gather separated pieces of food together for easier pickup. None of them can handle sandwiches.
European Pat. No. EP 0 523 292 A1, Michael Topping, 1991, discloses a robotic self feeding device consisting of a robotic arm, a cranked spoon, a control unit, a dish and a display unit. It utilizes one kind of utensil only, the cranked spoon with a coal-scoop front and scoops in a forward direction only. It does not use standard tableware such as forks and teaspoons, soup spoons or tablespoons. It cannot change utensils to suit different kinds of food in the same meal. It has no means to handle sandwiches It It has no means to cut food into smaller pieces. It can retrieve food only from a rectangular dish, not from standard round plates and bowls. Food must be carefully laid down in strips the width of the spoon in this rectangular dish.
Although this device has a sequence of operation, it does not contain a hover mode. The user must step through the stripes of food one by one to get to the one they want. The food preparer must prepare food of a limited range of consistencies and lay it out in an unnatural pattern of stripes, rather than putting it in in areas on the plate in the customary manner.
DeVARxe2x80x94the Desktop Vocational Assistive Robot, H. F. Machiel Van der Loos, PhD et al of the Department of Veterans Affairs Medical center, Palo Alto, Calif., and Stanford University Mechanical Engineering Dept.415-493-5000x5971, vdl@roses.stanford.edu. Use of DeVAR for self feeding is documented on a videotape entitled xe2x80x9cDinner with a Guestxe2x80x9d,1989. The video discloses a small industrial robot arm mounted on a round table. The user requests a programmed routine via voice input. The robot picks up a fork. The user requests motions in x,y and z directions until he has speared a piece of meat. He then verbally requests a preprogrammed routine to bring the fork to his mouth. He does a similar task with a spoon.
There is no operating sequence, only a set of preprogrammed routines, all of which are always available. There is no hover mode in which control is reduced to two directions in the horizontal plane and in which the utensil is constrained to remain over the food vessel. This makes the acquisition of food tedious and fatiguing, requiring constant attention. No interface besides voice is provided so people with no speech cannot use it. Each set of preprogrammed motions is requested via an unique spoken command. Because there is no operating sequence the user cannot proceed to the next logical step in the eating process by using a repeated command or actuation method each time.
DeVAR has only a simple gripper and can only pick up and grasp a utensil. It cannot operate a specialized grasping utensil such as a tong.
As can be seen, a number of self-feeding devices have been developed and two are currently on the market. However none of them permit handling such a wide variety of foods as my invention. None can operate utensils such as tongs. None has a hover mode and none offer the easy and intuitive use that my self-feeding apparatus provides.
In accordance with the current invention a self feeding apparatus with hover mode comprises a robotic arm, a set of food holding vessels, a set of eating utensils, a gripper, a control apparatus and an operating sequence whereby persons who may have severe paralysis can feed themselves.
Accordingly, several objects and advantages of my invention are:
a. It can pick up food from essentially any location on a plate or bowl or other food holding vessel. It does not require food to be laid down in stripes or other artificial patterns. This allows the user to eat in a conventional manner.
b. It does not require the use of unusual, non-standard dishes or trays. This allows the user to eat from the same dishes as others at the table or from restaurant dishes.
c. It allows the user to flexibly choose the food they want by controlling the motion of a utensil over the food. This makes the process of eating more natural, easier, and intuitive.
d. It can handle a wide variety of foods.
e. It can cut food. This means that food preparation need not he as time consuming as with other self-feeding devices.
f. It can automatically gather together food pieces which have become separated for easier pickup.
g. It can handle sandwiches.
h. It can be operated by people with a wider variety of disabilities than other self-feeding devices by use of a wide variety or control methods.
i. It can use unmodified eating utensils.
j. Further objects and advantages of my invention will become apparent from a consideration of the drawings and ensuing description.